Internal combustion engine



Spi W, W35. w. s. SMITH www INTERNAL COMBUSTION ENGINE vFiled Ap1-11 12, 1954 2 sheets-sheet 1 ATTORNEY Sem; w, w35.

W. s. SMITH 2,09%,6922

INTERNAL COMBUSTION ENGINE Filed April 12, 1954 2 sheets-sheet 2 Patented Sept. 17, 1935 PATENT OFFICE f INTERNAL coMBUs'rIoN ENGINE Walter S. Smith, Old Fort, N. C., assignor to The Shore Corporation, Dover, Del., a corporation of Delaware Application April 12, 1934, Serial No. 720,169

4 Claims.

l This invention relates to internal combustion engines and has particularly to do with a construction providing improved lubricating and `cooling of the piston and cylinder portions thereof. 'Ihe engine of this invention is especially well adapted for the burning of the usual hydrocarbon fuels including not only gasoline but those materially heavier than gasoline, which heavier fuels, in ordinary engines, have a pronounced tendency to pass down beyond the rings of the pistons and dilute crankcase or lubricating oil to Va condition not suitable for lubrication of moving parts.

In the drawings, which illustrate preferred forms of the invention,-

Fig. 1 represents a vertical cross sectional View of one form of the engine of this invention including a-separate guide portion between the crankcase and cylinders of the engine;

Fig. 2 is a similar vertical cross sectional view showing a modied form of engine in which the guide portion is integral with the cylinder block -a-nd upperV crankcase portions of the engine;

Fig. 3 is a vertical view, partly in cross section,

Yshowing the assembled cylinder and guide portions of the engine of Fig. 1;

Fig. 4 is a partially cross sectioned View taken on line 1 4 of Fig. 3, illustrating the guide portion of the engine of Figs. 1 and 3; and

Fig. 5 is a cross sectional detail showing the lower part of the piston including the oil control ring thereof.

Referring to the drawings in which like numerals represent like parts, and particularly to Figs. l, 3 and 4,-the engine of this invention includes a cross-head piston generally designated 2 having an upper portion 4 of large diameter and a cylindrical lower portion 6 of lesser diameter with an intermediate portion which may be of still less diameter. The upper portion of the piston is equipped with lsuitable compression rings 8 which operate in contact with the cylinder barrel Ii). The lower portion 6 of the piston operates within a guide box including guide portion I2 to which is imparted the side thrust of the connecting rod. The guide portion I2 is cooled by means of an encircling water jacket I4 to which water is admitted as by the port I5 and, after circulating about the guide portion l2 is discharged from the jacket I4 through the port I6 into ,the

pipe IB leading into the water jacket 2li surrounding the cylinders I0, from which jacket the water is led in the usual manner.

Thus, in the embodiment described, the cooling Water first cools the guide portions I2 and (Cl. 12S-170) then continues on to cool the cylinders by circula-tion in the water jackets 2li before being discharged from said jackets 2li.

The pistons are cooled by the circulation of Water in the jackets I surrounding the guide 5 portions I2 as well as the water circulation in the jackets 20. The top portions of the pistons 2 are provided with the usual compression rings 8, before mentioned, and the bottom or smaller diameter portions 6 are provided with oil control 10 rings 24 which scrape lubricating oil fromy the insides of the guide portions I2 and direct the lubricating oil thus removed into the interior of the pistons through the passages 24a as shown.

To permit the movement of the pistons of the 16 engine without interference due to air, the guide box I2 is provided with openings 26 connecting the annular spaces formed between the cylinders I0 and the guide box I2 and which except for openings 26 would be sealed at one end by the 20 compression rings 3 and at the other end by the fit between the lower portion of the piston 6 and the guiding surface of box I2. Such openings 26 are suiicient in number and size to minimize any material resistance to the pistons reciprocating 25 movement by reason of the air in the lower part of the cylinders around the pistons. The openings 26 lead to spaces 28 surrounding the guide portions of the pistons and may be connected to other pairs of cylinders by means of the open- 30 ings 30 as shown in Figs. 3 and 4. The openings at the ends of the engine may be either plugged or screened. When the engine is to be used for boats or elsewhere in enclosed engine rooms or indoors, the openings at the ends of the engine 35 are plugged and a pipe connection made with the space 28, for example, by means of a pipe connected in lieu of the plug 29. Thus, any pressure which might tend to build up byV reason of slight leakage down past the upper piston rings 40 is'relieved. The air circulation is confined Within the engine to the extent permitted by the opposing movements of the pistons. As is evident from the structure shown in the drawings, the air in the passage 28 is cooled by means of the water- 45 jackets I4, into which the cooling water is preferably led in the rst instance, and in turn the air upon entering the annular spaces beneath the top portions of the pistons assists in cooling the intermediate portions of the pistons. if the cylinders of a given engine are cast enbloc, the space 28 may run from end to end without the necessity for joints as between the openings 30 of Figs. 3 and 4 where the cylinders are shown as cast in pairs. Whichever way the en- 55 Naturally, 50

gine be constructed, the guide box may in many instances, be applied to existing engines by assembling it between the separate cylinder and crankcase portions of the engines.

Referring to Fig. 2 of the drawings, there is shown an engine in which the guide portion I2 is integral with the cylinder block and upper crank case portion 32 of the engine. This structure in its functioning is the same as that of Figs. 1, 3 and 4 and provides for the cooling of the pistons by guide portions l2 in turn cooled by the water jackets I4, and also by the water jackets 20. The circulation of air between the upper cylinder portions of the engine beneath the larger ends of the pistons is through openings 26 and spaces 28 as described in connection with Figs. l, 3 and 4. A connection may be provided to the space 28 in either form shown so that any excess lubricating oil and/or fuel that may collect can be drained therefrom, for example, a suitable pipe or drain connection may be made in lieu of the small plug 29 at the bottom of the space 28 in each of the structures. In practice, only a very slight amount of lubricating oil collects and that due to oil which works up past the oil rings 24 in the lower portions of the pistons. The lubricating oil which does work past serves to provide lubrication and ring seal for the top portions 4 of the pistons. The oil rings 24 are preferably so placed that when the pistons are at top dead center, the oil rings are still housed within the guide portions. In this manner the creeping of lubricating oil past the lower portions of the pistons is minimized and controlled to the amount required so that wastage of lubricating oil is effectively prevented. It will be seen that the lubricating oil can, in no event, be contaminated or diluted by any leakage past the pistons. Preferably, as shown in the drawings (Figs. 1 3 inclusive) the lower portion 6 of the piston is lubricated by force fed oil from the space 34 in the hollow crank pin through the radial passages 35, connecting-rod channels 36, radial channels 31 in the wrist pins and wrist pin bores 38 the bores being open at the ends and the oil free to iiow therefrom through the annular members 39 .to the inner surfaces of the guides I2. The upper ends of the pistons run somewhat hotter than the lower ends which is conducive to good combustion vand the lower ends of the pistons which take the side thrust are effectively cooled by the surrounding water jackets and provided with lubricating oil as above described and from crank case spray with the amount thereof controlled by the oil rings 24 which function as a lubricating oil barrier between the lower and upper portions of the pistons.

Having described my invention, what I wish to claim and secure by Letters Patent isz- 1. An internal combustion engine, having in combination, a crankcase, a plurality of water cooled cylinders, crosshead pistons in the cylinders, each of said pistons having a top portion of larger diameter than the lower portion thereof, piston pins in the lower portion of each of said pistons, compression rings in the top portions of said pistons, water-'jacketed tubular guides for the lower portion of each of said pistons to cool the same and also cool a wall portion of an air passage along the engine, said passage communicating with the annular spaces beneath the top portions of said pistons and above the said guides to relieve pressure in said annular spaces, said spaces being separated from the bore of said pistons by the piston Walls.

2. An internal combustion engine, having in combination, a crankcase, a plurality of Watercooled cylinders, crosshead pistons in the cylinders, each of said pistons having a top portion of larger diameter than the lower portion thereof, piston pins in the lower portion of each of said pistons, compression rings in the top portions of said pistons and oil rings in the -lower vport-ions thereof, water-jacketed tubular guides Afor the lower portion of each of said pistons to cool the same and also cool a wall portion of an air passage along the engine, said passage communicating with the annular spaces beneath the top portions of said pistons and above the said guid to relieve pressure in said Aannular spaces,

3. An internal combustion engine, having in combination, a crankcase, a plurality of Waterjacketed cylinders, crosshead pistons in the cylinders, each of said pistons having a top portion of larger diameter than the lower portion thereof, piston pins in the lower portion of each of said pistons, compression rings in the top portions' of said pistons, water-jacketed tubular guides for the lower portion of each of said pistons to cool the same and placed and adapted to receive the side thrust thereof, and an air passage vrontacting the exterior of at leastsome of the waterjackets of said guides and connecting at least some of the cylinders to provide free communication between the annular spaces beneath .the top portions of said pistons.

4. An internal combustion engine, having in combination, a crankcase, a plurality of waterjacketed cylinders, crosshead pistons in the cylinders, each of said pistons having a top portion of larger diameter than the lower portion thereof, piston pins in the lower portion of each of i.

said pistons, compression rings in the top portions of said pistons, water-jacketed tubular guides with the water-jackets thereof connected with the cylinder water cooling system for the lower portion of each of said pistons to cool the same and also cool a wall portion of an air passage along the engine, said passage providing n substantially wholly enclosed passage connecting the cylinders, said passage .having a pipe connected therewith to relieve any pressure therein. l

WALTER S. SIMITH. 

